Hi I found a 12 bolt at a nearby junkyard, it is already removed from the car but looks like a Chevelle 12 bolt. Here is every number I could find.

KDC 005 2

GM53

12345
87 (7 or 8)0

L141

3969278NF

(O or C)ON2

From what little I could find is that it is a 12 bolt 2.73 non posi built at the Buffalo plant in January on the second shift. Is there any way to find out what year car it came out of? Thanks for any help.

L141 appears to be the date code.
L - December
14- day of month
1 - 1971

So, it would be appropriate for a 1972 Chevelle L48/350-4